According to statistics, P2P (peer-to-peer) data accounts for 60% of the total Internet traffic, and it shows a tendency of continuous increase. In enterprise and service provider networks, P2P traffic is hard to control and thus occupies much of the bandwidth resource, thereby causing great time delay and small speed occur in other network applications.
IP data stream on the network is mainly based on the TCP protocol (Transmission Control Protocol) or the UDP protocol (User Datagram Protocol). Wherein, the TCP protocol is one kind of reliable transmission protocol which has congestion control itself and is sensitive to network delay and packet loss. In conventional traffic control, TCP traffic can be controlled very well by usage of buffer delay and packet loss. However, with the development of the Internet, P2P traffic base on the UDP protocol is occupying more and more network bandwidth. Since its own congestion control is imperfect or absent for such UDP traffic, it is insensitive to time delay or packet loss. When employing a traditional method for traffic control, it is still difficult for senders to slow down the sending rate on its own even when UDP data is dropped. In this case, the continuous packet loss is a waste of the bandwidth in turn.
Regarding the traffic based on the TCP protocol, when a host sending data packet has detected the packet loss, it will slow down the sending rate to avoid congestion actively. Nevertheless, applications based on the UDP protocol such as a P2P streaming application will not slow the rate for packet loss due to the shortage of traffic control mechanism. Besides, the traditional traffic control method is incapable of controlling the external network traffic, and it causes a waste to the external network bandwidth for continuous packet loss. On the other hand, overranging traffic not only wastes the external network bandwidth, but also leads to small speed and great time delay of other applications since it occupies their bandwidth. In particular, if the P2P is out of control in an enterprise network, the bandwidth resource of some key businesses is always unable to be guaranteed, which further influences the normal business operation.
In the prior art, upstream bandwidth and downlink bandwidth are defined and controlled separately. Generally speaking, the network traffic control only focuses on the downlink bandwidth of the traffic, while the control object for the upstream bandwidth is always not clear. Moreover, the proportional relationship between the upstream and downlink bandwidths varis with the specific traffic characteristics, and the actual upstream traffic usually cannot reach the prescribed upstream bandwidth.